HOUSTON — Is the United States really on the verge of putting weapons into orbit? Careless usage of provocative terminology appears to have converted a fairly routine upcoming military space test into a cause celebre for international arms control, and a potentially hot topic for the presidential race.

Internet bulletin boards are abuzz over a test planned by the U.S. Missile Defense Agency later this year, involving a payload called the Near Field Infrared Experiment, or NFIRE. The test is aimed at perfecting a sensor system that could track and destroy enemy missiles.

NFIRE would be sent into space aboard a commercial Minotaur launcher from NASA's Wallops Flight Facility in Virginia. Once the satellite is in orbit, a small sensor platform would be deployed, and try to get as close as possible to the rocket plume of another missile.

That platform happens to be a modified warhead, originally designed to knock down enemy missiles in the Pentagon's experimental short-range defense system. When the warhead is used in a missile defense system, it's known as a "kill vehicle." That name has carried over for the NFIRE test — and that is what's causing all the trouble.

For NFIRE, the kill vehicle's fangs have been pulled: It lacks the steering jets that would be required to ram a target in space. Pentagon officials told MSNBC.com that this kill vehicle couldn't kill anything.

But the mere fact that the thing is still called a kill vehicle has set alarms ringing around the world: The Moscow Times said NFIRE would mark a "sinister milestone," when the United States would break "a long-held taboo and launch the first weapon into the global commons of outer space." ABCNews.com called it the "first real step" toward the "unprecedented weaponization of space."

The Pentagon sources acknowledged to MSNBC.com, on condition of anonymity, that NFIRE is associated with space research for a future weapons system. But they said the system itself would not necessarily be based in space — nor would it attack "space objects." It's a subtle distinction, but one worth exploring in depth, particularly in light of the media alarm.

The actual mission
NFIRE is part of the Pentagon's research for developing what's known as a boost-phase missile defense system. The idea is that soon after an enemy missile is launched, an interceptor missile would blast off and home in on the infrared signature of the enemy missile's hot rocket exhaust.

In this scenario, the interceptor would indeed maneuver itself to knock the missile out of the sky. But the job would have to be done during the boost phase — before the enemy warhead reached outer space. Once the missile's fuel is exhausted and the enemy warhead or satellite is coasting, the infrared sensors wouldn't do any good.

That's not to say Pentagon officials haven't thought about basing weapons in space. In fact, they've been thinking about it for almost a half century. But a space-based system would require 100 or more separate satellites, and Pentagon officials say NFIRE doesn't represent any move toward such technology.

In this case, the term "kill vehicle" refers to a category of existing space vehicle, not to its function on this test flight, the Pentagon officials insisted. So whose bright idea it was to use a name bound to spark controversy? MSNBC.com found out it was so named by the engineers who built it.

'Kill vehicle' not quite dead
Still, the macho boosterism of flaunting a "kill vehicle" on a space mission shows up in a number of forums. In February 2003, when the Pentagon's Missile Defense Agency reported to Congress on its upcoming research, it expressed pride in the kill vehicle, even if the one on the first NFIRE test would be a non-maneuvering one: "The Generation 2 kill vehicle (KV) will be integrated into the experiment payload," the report stated, adding that such platforms would be "the first KVs with the performance to reliably achieve boost phase intercept."

The non-weapon status of this particular piece of flight hardware thus seems to be purely a matter of configuration, not ultimate capability.

And just a couple of weeks ago, at a March 25 budget hearing of the Senate Armed Services Subcommittee on Strategic Forces, a Pentagon official was asked specifically about NFIRE and space-based weapons.

"It is my understanding that this portion of the program would enable MDA to develop technology that can be applied to space-based weapons," Sen. Daniel Akaka, D-Hawaii, told Air Force Undersecretary Peter Teets. "My question to you is, is the NFIRE program intended to pursue space weapons capabilities? If not, what safeguards are being placed on the NFIRE program to stop it from turning into such a program?"

"It is true that the kind of capability that NFIRE will have could, with a different concept of operations, be used as a space-based weapon capability," Teets replied. "But there's no such concept of operations that I'm aware of that is under consideration at this point in time, and this NFIRE sensor will indeed be a sensor that looks at an infrared plume real close up and personal."

A modified kill vehicle had to be used for the test, Teets said, because "I don't know how else you can do that — I mean, if you're going to get close to it, you're not going to do it with an airplane."

Pentagon officials insisted that they didn't consider the NFIRE experiment to be a step toward "weaponizing" space. Even such a plan were approved by the government, one official said, it would be several years more "before we will consider launching even a small experimental space-based interceptor satellite constellation."

Tilting at space windmills?
So if the NFIRE test is as described by the Pentagon, it wouldn't put an actual weapon in space, and it wouldn't be intended to test a space-based weapon system. But even if any of that were true, NFIRE wouldn't represent "the first time in history that any nation has put a weapon in space," as claimed by The Moscow Times.

In fact, there is significant irony that such an assertion would appear in a newspaper in Russia. Space historians realize that the Soviet Union excelled at putting weapons into orbit during the Cold War, weapons without any American counterpart. First there was a space-to-space orbital killer-satellite, then a military jet interceptor cannon that was mounted on a manned space station in the Salyut program.

In 1986, the first test flight of the Energia super-booster carried a 100-ton test payload for an antisatellite beam weapon. Other programs involved placing dummy thermonuclear weapons into low orbits for first strikes against North America. All of these projects collapsed with the fall of the Soviet Union, but their erstwhile existence cannot be denied by any serious investigator.

As for NFIRE's missile plume measurements, they are follow-ons to observational programs the Defense Department has performed for decades, from the ground, from aircraft, from unmanned satellites, and even in 1991 from a space shuttle flight. Soviet cosmonauts made similar observations from Salyut and Mir space stations.

The new tests could well contribute engineering data for the design and development of an antimissile system whose warheads could be based on land, on ships, or even potentially in space. These potential strategies are worthy of public debate, but the only hope for a productive discussion is a firm foundation in reality — and the latest alarms over "weapons in space" fail to provide this.